Softgels, such as softgel capsules, are formed by a variety or processes, including a rotary die encapsulation process. In the traditional rotary die process, encapsulation machines form two flexible gelatin sheets or ribbons, which are synchronously guided over rollers and fed to and between two dies. For example, a left and right ribbon each pass over rollers that feed the ribbons to (and between) two mated die rolls. The die rolls, whose surface architecture determines the size and shape of the resultant softgels, cut the softgel shells from the ribbons as the ribbons roll between the die rolls. A positive displacement pump simultaneously delivers the fill material into a heated wedge that sits between the rotary dies. The pump injects fill material, such as a liquid fill material, into the die cavities between ribbons just before the die rolls cut the ribbons and seals the two cut halves of the ribbon together to form a softgel. The softgels are then dried and allowed to harden.
While the rotary die manufacturing process is sufficient for making rounded or oblong softgels, using this process to manufacture shapes other than rounded or oblong forms has proven challenging. This is principally because the seam thickness where two halves of the softgel shells come together varies greatly. More particularly, the regions of gelatin ribbons that first enter die rolls form a leading edge on the resultant softgel, whereas the regions of the gelatin ribbons that follow behind form a trailing edge on the resultant softgel. Typically, the seam thickness at the trailing edge is only a small fraction of the wall thickness of the softgel. For example, the seam thickness of the trailing edge can be as little as 20% as thick as the wall thickness of the softgel. Hence, the thin seam thickness at the trailing edge cannot, for example, withstand certain manufacturing processes, such as those that seek to produce certain softgel shapes. Additionally, the thin seam at the trailing edge leads to breakage of softgel during handling of the product and leakage of the fill material. The thin seam thickness at the trailing edge can also be problematic for rounded or oblong softgels, such as during the manufacturing process and shipment.